The invention relates to the field of concrete form work. In particular, the present invention provides a novel form, stake, and form assembly, and method of making the same, for use in the placement of concrete.
Concrete form and stake assemblies are used extensively for the placement of concrete in order to shape and contain the concrete, to create such things as sidewalks, driveways, footings, and concrete slabs. Preparation of a site for the placement of concrete, involves, after leveling off the area, erecting a frame to contain the concrete. Erecting the frame for concrete placement commonly involves: the placement of stakes; attaching the form members to the stakes by nailing the form into place; and ultimately forming a cavity within the completed assembly of forms into which concrete is placed. To cover a length larger than any one form, forms in the past have been abutted end-to-end to cover the additional length necessary. The concrete is placed into the cavity within this frame. The frame is then removed once the concrete has set.
Frames erected for the placement of concrete conventionally are constructed of lumber. Often, in order to accommodate the various dimensions of frames, the lumber must be cut to shorter lengths to accommodate specific projects, making it unlikely the lumber will be used on a subsequent project of differing dimensions. Further, the necessary nailing or other means of attaching the wooden forms to the stakes results in damage to the lumberxe2x80x94the end result being that the lumber is likely consumed in the placement of one slab of concrete. Another problem with using lumber is that it does not bend well to form a radius. As a result, other materials may be necessary to form a radius or significant time is expended in shaping the wood. Furthermore, because concrete tends to stick to the wood, the wood forms cannot be removed at the end of the day. Instead, the worker must return on a second day to retrieve the forms after the concrete has sufficiently set.
Some alternatives to wooden forms have been used. One such alternative is to use a flexible plastic form. These forms have the ability to flex to accommodate various grades of land and to accommodate slight curves. However, to accommodate lengths longer than any one form, the plastic forms are abutted end-to-end. Thus, in order to accommodate a specific length it may be necessary to purchase a specific length form or to cut a form to the specific length, both of which are inefficient and costly.
One solution to the drawbacks of both the wooden and plastic forms has been to provide a metal formwork board that will not be consumed during one project and can therefore be used in subsequent projects. Traditionally, these metal formwork boards were abutted end-to-end, as was the case with the wooden forms, to accommodate lengths longer than a single form board. However, the problem with such an assembly is that without specific lengths of metal forms, it is difficult to modify the forms to accommodate the various lengths necessary to build an appropriate size frame.
Thus, as disclosed in U.S. Pat. No. 5,655,336, one attempt to accommodate specific length frame sizes was to use a telescopic metal form board that extends to various lengths. As a telescopic form, the form can be expanded to a desired length within a limited range to accommodate various frame sizes. A problem with telescopic frames is, however, that the frames are generally of a C-shaped cross-section and consist of successively smaller C-shaped components fitting within a larger C-shaped component. Due to the C-shape and function of the telescopic components, the successive telescopic forms must be either abutted end-to-end or slid within each other to accommodate lengths greater than any one telescopic form. As a result, the assembly and disassembly of the forms, particularly for forms that are slid within one another, requires sliding the C-shapes together or apart before securing the forms in place. Unless these forms are kept extremely clean, the C-shape forms will not slide within one another, adding unwanted additional time and energy for a worker to thoroughly clean the form and to slide the forms together before securing the form to the ground. These forms, due to the C-shaped cross-section cannot be used to create a radius, or curved portion for the frame. Furthermore, the telescopic forms are quite bulky, due to the series of components that must be slid within one another, requiring significant space for transport and storage, as well as adding additional weight. Additionally, the C-shape of these forms is difficult to manufacture.
Problems also exist with respect to the stakes and the structure for securing the stakes to the form boards. Various types of stakes and methods of securing the stakes to the form boards have been used to secure the form boards in place on the ground. For example, simple metal stakes of various lengths have been used. These stakes are driven into the ground, and often have holes drilled through them so as to allow a nail to be driven through the stake and into the wooden form board to secure the board in place. Wooden stakes could also be used with nails driven through them and into the form boards to secure the forms in place. Alternative stake systems that have been used consist of holes vertically spaced throughout the form members so that a stake may be inserted into the hole and subsequently driven into the ground to secure the form in place, or alternatively, using a clip or other means to attach the stake at the outside of the form member.
The problems with these prior stakes are various. First of all, stakes that require nails to be driven through same result in damage to the form boards as already discussed. Furthermore, these stakes require the worker to have additional materials available while constructing the frame. Stakes that require vertically driven holes in the forms require that the stakes be placed in certain exact locations, not allowing for the adjustments needed for variations in terrain or other factors. Additionally, for those telescopic forms that require the stake to be driven through the form member, the placement of the holes in the form boards limits the distances the form boards can be extended in order to insert the stakes through the forms. Finally, for stakes that are set to the side of the forms, two problems arise. First, the weight of the forms is not balanced properly on the stake, resulting, if the stake is not driven in far enough, in the possibility that the form and stake assembly may lean to one side. Second, the side attachments for the stakes are additional components that the worker must carry and have available for assembly of the frame, creating additional set-up time, the requirement of more storage space, and more items to transport.
Furthermore, the above described stakes are not adequate to be used simultaneously for placement of concrete in a trench footing and the creation of a concrete slab. Prior stakes typically are straight, not including any angles or offset, resulting in the attachment of a concrete form board directly above the location of placement of the stake into the ground. Typically, in creation of a footing, a trench is first formed and concrete is placed into the trench. Subsequently, the concrete slab is created above the filled trench by the use of concrete form members and stakes. However, this is a two step process, requiring additional time and materials. To limit this to a single step process the above-mentioned stakes are placed into the ground prior to filling the trench. The result is that the side wall of the trench is likely to collapse due to the close proximity of the stake to the trench to create a concrete slab above the footing. Therefore, to create a trench footing simultaneously with the creation of a concrete slab, an offset is needed in the stake to provide space between the wall of the trench and the location of insertion of the stake into the ground to avoid this problem of trench cave in.
In view of the foregoing, therefore, a need exists for a concrete form assembly that is light weight, easy to clean, easy to manufacture, reusable, easy and quick to assemble and disassemble, and capable of conforming to any length, for use with a ground engaging member that does not result in damage to the form, is simple to use, and comprises few parts. A need also exists for radius forms to be used with such an assembly, and for stakes for use in the creation of a trench footing simultaneously with the creation of a concrete slab without the cost of additional materials or time.
The difficulties encountered in the prior art are substantially eliminated by the present invention.
An object of the present invention is to provide a novel form, stake, and form assembly for use in the placement of concrete.
A second object of the present invention comprises form members that overlap one another, allowing simple and quick assembly and disassembly of the concrete form and stake assembly.
A third object of the present invention comprises form members that overlap so as to adjust to any length necessary for frames of a particular dimension.
Another object of the present invention is to provide thin concrete form members so that the forms may be overlapped without forming a significant ridge on the concrete face of the form.
A further object of the present invention comprises overlapping metal forms that are easy to clean, but still function effectively with debris remaining on the form.
An additional object of the present invention comprises concrete form members that are light weight, and thin, to accommodate easy and compact storage and transport.
A still further object of the present invention comprises radius form members that function in the same manner as non-radius forms, yet provide the ability to flex or bend in either direction.
One more object of the present invention comprises stakes that fit functionally within an extension of a concrete form member for resting the form on the stake and for easy assembly and disassembly of the concrete form and stake assembly.
Another object of the present invention comprises ground engaging members that have attached locking mechanisms to provide for securing the ground engaging member in place without separate additional materials.
A further object of the present invention comprises providing a novel stake for use with a footing.
By the present invention, it is proposed to overcome the difficulties encountered heretofore. To this end, an assembly for concrete forms for use in the placement of concrete, in which the concrete forms are light weight, easy to manufacture, easy to clean, and capable of being stacked in a compact fashion, is provided. The concrete form assembly comprises a first longitudinal form member with a first end and a second end; a second longitudinal form member with a first end and a second end; a ground engaging member in contact with at least one of the first and second longitudinal form members; and the second end of the first longitudinal form member slidably overlapping the first end of the second longitudinal form member, allowing the combination of first and second overlapping longitudinal form members to be adjusted for length by varying the amount of longitudinal overlap.
These and other objects will become apparent upon reference to the following specification, drawings, and claims.